Thanks Ed!  Lovely guitar.  I think you are referring to celluloid
(developed in mid-1800’s, flammable, smells a bit like camphor or Vick’s
Vapo-rub when scratched or dipped in hot water)?  Turns up in various
objects at flea markets.
   In contrast, ‘modern’ plastics have no smell (except for phenolics
-smell like formaldehyde & phenol -aka Bakelite, the original thermoset
plastic that was used in pretty much everything 100 years ago).  Not an
expert but remembering old mat sci lectures from engineering skule a
lifetime ago...
Cheers from Waterloo
Claudio